argiope

I’m sure most of you would’ve read or heard about the beastly female spiders that devour their puny male mates after copulation, biting their heads off soon after they erm, serve their biological imperative.

While I can’t deny that it is – generally speaking – true, things aren’t quite as bad as that. Many male spiders survive at least 2-3 encounters with females. 🙂

Many male spiders are still tiny little squirts though – they make a great case study of sexual dimorphism in nature. The male Argiope spider is barely a quarter of the female’s size. And while the female is strikingly colourful, the male is a dull, featureless brown. Come mating season, they usually build secondary webs close to a female’s much larger, better web… and you know, just hang around.

There’s no real punchline to this post, all that text was just build-up to what I thought was a pretty neat picture. 🙂 Thassal for today.

Today’s post, like many others before it, starts with an Argiope spider. Though they are quite interesting in their appearance, you’re likely to be quite bored of them by now, if you have been following this blog for any length of time. In fact, the photo just below is rather mediocre compared to what I usually share.

But wait. The Argiope is not the only thing seen in that picture, is it? No, there’s a second, smaller spider in the top right corner, messing around with a dead insect wrapped and kept as leftovers.

Turns out that the second spider is a Dewdrop spider, genus Argyrodes. And it’s up to no good. Take a look at the collage below.

Most orb-web spiders trap and kill prey when they find them, and they wrap them up in silk and tie them on their web to one side, pretty much like what you can see in these pictures. And the Dewdrop spiders steal them!

Dewdrop spiders build small webs quite close to those of larger spiders, such as this one. Often their web is in a plane parallelt to the larger spider’s, but set to one side. They also sneak in a couple of strands between the two webs for ease of access. And when they chance upon a morsel small enough for them to nick, voila. Now you see the silk ball, now you don’t. The Sting glowed blue when Sam rescued Frodo from Shelob, the Argyrodes just shines silver.

Kleptoparasitism is the technical word for it, parasitism by theft. It seems to be all the rage in the animal kingdom. The Arachnid world has dewdrop spiders, the birds have skuas, and we humans have pimps, child peddlers and other scum of the earth.

Yesterday I’d posted about an Argiope spider that had lost two of its legs in a skirmish that is all to frequently replicated in nature, regardless of scale.

And lo! I find the same spider again after 4 days, to see that it has regrown them.

Online searches showed me that limb regeneration is usually only possible among juvenile spiders, the notable exception to this being tarantulas. This was certainly not a fully mature Argiope, still having to go through a few molting stages to get there.

What’s fascinating is that the legs took but 4 days to develop that much. I wish I’d caught the complete cycle of regeneration. Just when you think that you know everything there is to know about spiders, boom. They hit you on the head again with some insane badassery.

The Gulf of Mannar coast of Tamil Nadu is a rather interesting place, even outside of all the critter pics from there that I’ve been putting up. Falling largely in the shadow of the Western Ghats, the whole region is quite arid in nature.

Back in the ’70s and ’80s, mad pamphleteers and “development experts” spearheaded this massive effort to promote seeding of Prosopisjuliflora, a large, thorny and wholly unpleasant shrub. Hailing it as the saviour of our deserts and the provider of alternative livelihoods, Prosopis was promoted with reckless abandon, touted as a great source for charcoal, firewood and all things wonderful.

Today, Prosopis is a highly invasive species that’s spreading everywhere. The shrub (I say shrub, but really, they’re these low-slung trees that form a vast and impregnable network of branches that can spread across quite an area,) cannot be eaten by livestock of any stripe.

Such trivial things can never stop spiders, though. On Prosopis bushes by the sea in Keelamundal on the Ramanathapuram coast, I found the highest density of spiders anywhere, thus far. On most bushes, I could find more than multiple spiders in every cubic foot of space. To get one on my camera, I had to be really careful in not brushing through the webs of several others.

In the picture below, you can see a juvenile female Argiope in focus, an adult female at the bottom, and two diminuitive males of the same species out of focus on either side.

And if you take my word for it, there were some half a dozen more spiders to my right, some below the picture and several all around. Who knows, maybe even Cross spiders are as rampantly invasive as the shrubs that harbour them.

A lot of critters profiled on this blog have been from my workplace near Bommasandra, on the outskirts of Bangalore. We have a lovely little campus, with over two acres of area and less than a third of it built upon. The rest is filled with trees, lawns, and even little vegetable patches. Perfect for spotting critters of all shapes and sizes.

The problem though, is that we are located bang in the middle of an industrial area. Disturbingly frequent bad smells, sirens going off in the distance, and overloaded trucks always plying on the main road are the most routinely experienced consequences of the obviously well-regulated industrial area.

Behind our campus is a button factory. You know, an entire factory dedicated to making your teeny tiny buttons. Cute, right? NOT. Once every six months or so, I think they finish manufacturing large numbers of buttons and get them ready for the last round of processes: polishing. They polish the buttons by removing fine layers of plastic off the buttons… and into the air.

They stick on to everything. They get indoors, they mix in with the soil everywhere, all surfaces are spotted white… and they stick on to spider webs.

A spider’s web (especially when it’s an orb web, like the Argiope’s, above) works as a flytrap only because it’s all but *invisible* to flies and other insects. Once you stick big shiny wafers of plastic on the web, it kinda stops working.

Not all spiders go down without a fight though. Some Cyclosa spiders – this one likely being the Cyclosa spirifera(getting their first feature on TDC today) use the plastic to their advantage instead! Cyclosa spiders have been known to use litter, the remains of insects, dirt and just about anything to create blobs of gunk on their web, which act as decoys to the real spider should a predator attack.

The Cyclosa here promptly grabbed all the plastic stuck to its web and pulled it into the centre, as shown below, leaving the rest of its web remarkably clean. What could’ve starved the spider to death was instead used to improve its camouflage! All hail the mighty spider.